Go already
drosophila @ drosophila @lemmy.blahaj.zone Posts 0Comments 277Joined 1 yr. ago
drosophila @ drosophila @lemmy.blahaj.zone
Posts
0
Comments
277
Joined
1 yr. ago
While things like merging movements and so on is part of the story, it's not the whole story.
You see, by saying "traffic jams are caused by merging mistakes and so on" it kinda implies that if everyone drove perfectly a highway lane could carry infinitely many cars. In actually a highway lane has a finite capacity determined by the length of the vehicles traveling on it, the length of the gap between them (indirectly determined by how fast they can start and stop), and the speed they're moving.
There are finite limits for gap widths and speed determined by physics and geometry. As the system approaches these limits it becomes less and less able to deal with small disruptions. In other words, as more cars move on a freeway a traffic jam becomes more and more likely. The small disruption which is perceived as the cause was really just the nucleation point for a phase change that the system was already poised to transition through. If it wasn't that event then something else would trigger it.
It is interesting to note that once a highway has transitioned from smooth flow to traffic jam its capacity is massively reduced, which you can see in the graphs in the above link. Another interesting thing to note is that the speed vs volume graph, if you flip it upside down, resembles a cost / demand curve from economics, where volume is the demand and time spent commuting (the inverse of speed) is cost. If you do this you see something quite odd, which is that the curve curls up around itself and goes backwards.
This is less like a normal economic situation (the more people use a resource the more they have to pay, the less people use it the less they have to pay) and more like a massively multiplayer version of the prisoner's dilemma. For awhile the cost increases only slightly with growing demand, until a certain threshold where each additional actor making a transaction has a chance to massively increase the cost for everyone, even if consumption is reduced. Actors can choose to voluntarily pay a higher time cost (wait before getting on the freeway) to avoid this, but again, it's the prisoners dilemma. People can just go, trigger a traffic jam anyway, and you'll still have to sit through it + all the time you waited trying to prevent it.
Self driving cars are often described as a way to eliminate traffic jams, but they don't change this fundamental property of how roadways work. It's true that capacity could potentially be increased somewhat by decreasing the gap between cars, since machines have faster reflexes than humans (though I'm skeptical of how much the gap can really be decreased; is every car going to weigh the same at all times? Is every car going to have tires and brakes in identical conditions? Is the condition of the asphalt going to be identical at all times and across every part of the roadway? All of these things imply a great deal of variability in stopping distance, which implies a wide safety gap.), but the prisoner's dilemma problem remains. The biggest thing that self driving cars could actually do to alleviate traffic jams would be to not enter a highway until traffic volumes were at a safe level. This can also be accomplished with a traffic volume sensor and a stop light on highway on-ramps.
Of course trains, on top of having a way higher capacity than a highway lane, don't suffer from any of this prisoner's dilemma stuff. If a train car is full and you have to wait for the next one that's equivalent to being stopped at a highway on ramp. People can't force their way into a train and make it run slower for everyone (well, unless they do something really crazy like stand in the door and stop the train from leaving).
No better than what?
CRI is defined as how closely a light source matches the spectral emission of a thing glowing at a specific temperature. So, for a light source with a 4000 k color temperature its CRI describes how closely its emission matches that of an object that's been heated to 4000 k.
Because incandescent bulbs emit light by heating a filament by definition they will have 100 CRI and its impossible to get any better than that. But the emission curve of incandescent lights doesn't actually resemble that of sunlight at all (sorry for the reddit link). The sun is much hotter than any incandescent bulb and it's light is filtered by our atmosphere, resulting in a much flatter more gently sloping emission curve vs the incandescent curve which is extremely lopsided towards the red.
As you can see in the above link, there are certain high end LED bulbs that do a much better job replicating noon day sunlight than incandescents. And that flatter emissions profile probably provides better color rendering (in terms of being able to distinguish one color from another) than the incandescent ramp.
Now, whether or not you want your bulbs to look like the noon day sun is another matter. Maybe you don't want to disrupt your sleep schedule and you'd much rather their emissions resemble the sunset or a campfire (though in that case many halogen and high output incandescent lamps don't do a great job either). Or maybe you're trying to treat seasonal depression and extra sunlight is exactly what you want. But in any case I think CRI isn't a very useful unit (another reddit link).
One apple (223 g) is supposed to be 116 calories.
Damn Small Linux can run a graphical desktop environment with as little as 16 MB of RAM (although 24 is recommended).
That really makes me want to see a Wii with a mouse and keyboard plugged in displaying a spreadsheet or something. Unfortunately DSL only supports x86. Theoretically it could be ported to PPC like Void Linux was, though I don't know if all the tweaks they did to make the kernel and pre-installed packages as small as possible would make that harder.
There is already a Chinese EV that uses a sodium ion battery, the JMEV EV3.
It's a tradeoff of range vs price. The EV3 only has 155 miles of range, but thanks in part to its sodium ion battery it costs only $9220 new. Which is a price that will probably drop even more as more sodium ion plants come online and economies of scale kick in.
EDIT: even if your commute is 40 minutes long, driving 60 MPH the entire way, that range is enough to get you to work and back using a little more than half your charge. Given that it's also generally cheaper to charge an EV than pump gas, and there's less maintenance costs, I think there's absolutely a market for such a car.
lol, because that's definitely the shut-in stereotype.
"Honey I'm really worried about our son, not only has he not left the house for weeks, this morning I found a bag of coffee beans in his room that was produced by a worker owned coop in Honduras!"
Trying to create a cheap microwave burrito that's also healthy and filling seems like a pretty noble (if difficult) goal to me. Making it vegetarian also decreases its ecological impact (though I don't know whether or not Adams cared about that).
Trying to fortify each burrito with 100% of your daily vitamins was a really stupid idea though. It was unnecessary (just take a multivitamin if you feel like you need it), it made the burrito taste worse (Adams described it as "chalky"), and it was potentially unhealthy if someone were to eat multiple burritos per day (and thus receive multiple times the recommended daily dose of... everything).
An arch user defines "doesn’t break all the time" as "I have to read the news before every update and apply a manual intervention a few times a year, and there's only been like one time in history that an update made people's installs unbootable despite them taking those precautions".
A Debian user defines "doesn’t break all the time" as "I have a cron job running that periodically runs sudo apt update. I have no idea when it does this or what's changing when it happens and nothing bad has ever happened to me".
Like, the fact that unattended-upgrades comes pre-installed and enabled by default (for security updates) in Debian GNOME vs the fact that informant exists to force you to read the news in Arch before you update should tell you that the two distros exist in two different universes.
Krankenwagen
It's just a silly name for DPI, but it does exist.
https://en.wikipedia.org/wiki/List_of_humorous_units_of_measurement#Mickey
Adding on to what GreyEyedGhost said, since the year 2000 the price of solar power (per watt) has fallen by more than 50x. Because of this huge drop in price the installed solar capacity has been doubling every 3 years. That means that in the time since 2020 we've built more solar capacity than we did in the previous 20 years combined.
If that's not good enough then idk. Imagine holding any other technology to that standard. The model T came out almost 100 years ago for an inflation adjusted price of $27,000 and with an MPG of 7.5. ICE cars today are better in a lot of other ways but they are not 50x cheaper and they are not 50x more fuel efficient than that.
He must listen to arcane tomes in audiobook form while doing crunches.
the production of highly processed foods
Source?
The US congressional research service thinks EU subsidies are more spread out among all types of crops, including fruits and vegetables, whereas US policy focuses more on grains, sugars, dairy, and oil seeds: https://crsreports.congress.gov/product/pdf/R/R46811
That's not a direct subsidy of food processing of course, but the crops the US chooses to support ends up incentivizing it.
And this paper also makes it sound like subsidized crops in the US end up in processed foods: https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2530901
So we were talking about supply, not consumption. But regardless, yes americans choose to eat processed foods more on average. So?
Cultural factors are a thing but I think they're used far too often to explain away trends at the population level and the effects of public policy.
The US has lower rates of food contamination from e.g. Salmonella or E coli, which I think is what that study is measuring. However, I think food in the EU generally has superior, better tasting, ingredients. There are two reasons I believe this to be the case. The first one probably has a smaller impact than the second.
The first reason that in the US an ingredient must be proven to be harmful before the FDA is allowed to ban it. In the EU an ingredient must be proven to be safe before it is allowed in commercial products.
The second reason is that while both the US and EU have farming subsidies, the way these subsidies are structured means that in the US they tend to incentivize the use of high fructose corn syrup and the production of highly processed foods while in the EU highly processed foods tend to be more expensive and "whole foods" tend to be cheaper.
As a result people in the EU tend to eat less processed food as a percentage of their caloric intake:
Absent the effect of gravity hair strands have a tendency to straighten and spread out. Usually astronauts with long hair tie it up, but there are some pictures showing what this looks like:
Makes me wonder whether that's depicted in the manga.
Absolutely. The fact that 3 million people pass through Shinjuku station every day is a testament to that.
If all of those people lived in a city in the US it would be the country's third largest, behind NY and LA. (If we're going by the entire urban area instead of just within city limits it would be the 20th, just ahead of the Baltimore-Columbia-Towson metropolitan statistical area.)
All in a space that's smaller than most highway interchanges.
And that's not even using two-level train cars (which is where your figure for 360 people per train car comes from I think?).